Windows:If unable to rename all files in folder because of shortening failure files can get split
On Windows the individual file parts were within limits but the total path was greater than 259 for some files in a folder but not all and this meant shorten() had to do a truncate on some but then had duplicate names so we ended up with some files being renamed and some not so split over two folders.
1. We need to more intellligentally rename so name is valid
2. Ensure all files in grouping could be renamed or dont rename any of them
Fixed, totally rewritten
Note we currently rename each song as part of SongSave() but really we should try renaming all songs in grouping first as part of SongSaver() then we can do some checks across the whole grouping so we know that at least within the grouping there is no issue (always possibility there is some issue when actually do the rename due to an external event)
Addressing the intelligently renaming. We already look at the filename part and if total length is too long we shorten album part if in filename by amount required, if that not enough we do the same with artist. Now if still not enough we look for title and also shorten but shorten from front because the problem is most likely with Classical tracks whereby there is often alot of repetition in the title so to not create a filename with clash to other track on the album best to remove chars form start of title.